Baffle arrangement



Dec. 6, 1932. HUET 1,889,861

BAFFLE ARRANGEMENT Filed Sept. 20. 1930 I N VEN TOR.

A TTORNE Y.

Patented Dec. 6 1932 UNITED STATES PATENT OFFICE.

-A1\IDR-E HUET, or'ranrs, FRANCE, assrenon TO THE SUPERHEATER COMPANY, on NEW Yosx, N. Y.

BAFFLE ARRANGEMENT Application filed September 20, 1930, Serial No. 483,232, and in France May 5, 1930.

The prior art shows battling arrangements applicable to tubular heat interchangers and particularly to boilers or superheaters in which the battles are made up on the boiler or superheater tubes themselves which are placed in such relation over one part of thelr length as to direct the gases along the desired path. One way of making such baffling arrangements is that in which the tubes lying in one plane are bent back on themselves in that plane so as to fill up the. spaces between them and thus to form a closed baflie.

The present invention has for its object a bafiiing arrangement of this sort whose essential characteristic is that the corresponding branches of the several serpentine coils composing the tubular bundle which are normally disposed in different planes so that gas passages are left between them are at those places where baffles are to be provided carried into the same plane in such a manner as to be in contact with each other over a distance extending from one of the walls of the heating or superheating chamber to a pomt situated at a predetermined distance from the opposite wall.

The description which follows and whlch makes reference to the accompanying drawing and which is given by way of example will make clear the principle of the invention and the manner in which it can be carried out.

Fig. 1 is a longitudinal section on the line 11 of Fig. 2 of a separately fired superheater with my invention applied;

: Fig. 2 is a section of the same superheater on the line 22 of Fig. 1;

Fig. 3 shows a detail of it on a larger scale, Fig. 4 being a section on line 4-4 of Fig. 3;

Fig. 5 represents likewise on an enlarged 'scale a further detail of which Fig. 6 is a section on line 66 of Fig. 5.

These figures relate always by way of illustration to a separately fired recuperative superheater in which the hot gases coming from source 1 are directed by the tubes 2 and the passage 3 toward the superheating chamber 4, and after having traversed the latter are taken by the fan 5 which forces them in part toward the stack 6 while the other part is the several serpentine coils lying in said plane are bent into this plane so that theylie side by side over a part of their length and close off. for this part of their length the entire width of the chamber.

To complete the baflie onthe side toward the wall of the superheater chamber, the elbows 12 forming the ends of the branches 9 are enclosed, for'example, with a slight clearance between two horizontal angles13 fixed to thewall 14 of the superheating chamber and wide enough to make sure that the end of the baffle is closed. Beyond the return bends 12, the tubes are then bent and alternately offset at different heights in such a way as to again form two planes with spaces between the tubes for the passage of gases.

' The baflie 17 is formed in a way slightlydifi'erent. from the baflie 9 and shows a varia tion-of the manner in which the invention can be carried out.

In the case of the baflie 17 the adjacent branchesinstead of terminating in elbows or return bends at theend toward the wall of the chamber are at that end simply bent on alternately different radii and are therefore adjacent only at the point 18 where the bending starts. Between this point 18 and the wall 19 of the chamber, tightness is assured for example by a tile 20 lying on the tubes 17 and fixed to the wall by a bracket 21.

The different straight lengths of the tubes constituting the superheater bundle are, according to a known arrangement, of different lengths, the shortest of the lengths being exposed to the highest temperatures. In this way the different lengths expand by amounts approximately equal and the tubes constituting the bafiles are thus not subject to warping which would impair the tightness of .the battle.

WVhile I have described the invention as applied to a case where the several straight lengths of the elements are horizontally disposed, and the bafiles are therefore also horizontal, it will be obvious that this is illustrative only and that the invention is equally applicable to cases Where the straight lengths are at some other angle, for example vertical, the gas flow being generally horizontal, the battles also being vertical. Such variations are to be considered to be within the scope of the appended claims.

lVhat I claim is 1. A group of U-tubes arranged close together in parallel planes and having alternately greater and less widths and each having one of its legs in a given plane at a considerable angle to said parallel planes and eachhaving its other leg on the same side of said given plane, said legs in the given plane arranged to form a battle and the other legs arranged to permit the passage of gases therebetween. I

- 2. A group of elements, each comprislng a plurality of parallel, straight tube-lengths all in one plane, said elements being arranged side by side immediately adjacent to each other, the lengths of alternate elements being relatively staggered to permit gases to pass .in a direction generally transverse to the lengths and lengthwise of the elements except where it is desired to form a batfie at Which point-s a tube length of each element is in alinement with a tube length of every other element. I

3. A group of tubular elements arranged to abstract heat from gases flowing there through, each having a number of U-loops therein, the legs of said loops being spaced apart throughout portions of the group to permit flow of gases therebetween, and the group having a balile formed therein by a single leg from each of the elements.

t. In a heat exchanger the combination of a plurality of elements each comprising a plurality of straight tube lengths and return portions connecting them into a continuous unit for series flow, the lengths of each ele ment lying in a plane and the elements being arranged in adjacent vertical planes, one horizontal plane containing a straight length of each element, these lengths being in contact with each other and forming a baflle, the remaining straight lengths being arranged so any given horizontal plane contains straight lengths of only a part of the elements thereby permitting gas flow across these straight lengths.

5. I11 a heat exchanger the combination of a plurality of elements each comprising a plurality of straight tube lengths and return portions connecting them into a continuous unit for series flow, the lengths of each element lying in a plane and the elements being arranged in adjacent vertical planes, one horizontal plane containing a straight length of each element, these lengths being in contact with each other and forming a bafiie, the several return portions connecting the lastlying in a plane and the elements being ar ranged in adjacent vertical planes, a pluralityof horizontal planes each containing a straight length of each element in contact with each other to form baflles, the'remaining straight lengths being arranged so no horizontal plane contains a straight length of each element.

7 In a heat exchanger the combination of a plurality of elements each comprising a plurality of straight tube lengths and return portions connecting them into a continuous unit for series flow, the lengths of each element lying in a plane and the elements being arranged in adjacent vertical planes, at plurality of horizontal planes each containing a straight length of each element in contact with each other whereby battles are formed, the remaining straight lengths being rela tively staggered thereby permitting gas flow between them.

8. The combination in accordance with claim 7 and further comprising a housing enclosing the elements, the plurality of baflles being spaced alternately from opposite ends of the housing.

ANDRE HUET. 

